In connection with subsurface wells, such as a hydrocarbon well, it is common to arrange gauges, such as pressure or temperature gauges, within the well bore. As it is difficult to provide wireless communication from a gauge in this position to a surface or seabed location, a hollow cable is guided down into the well bore, clamped to a pipe string. The cable guides one or more conductors, such as electrical or optical conductors, down to a gauge housing. Before lowering the gauge housing and the hollow cable with the conductor down into the well along with the pipe string, the crew connects the conductor to the gauge with an optical and/or electrical connector. In addition a pressure resistant barrier between the inside and outside of the cable and gauge housing is established. Thus, the connector is maintained in a low pressure environment with a barrier to the downhole high pressure environment.
When used in connection with a subsurface well, the downhole gauge assembly may be mounted topside on a floating surface installation associated with a subsea well or on a land based structure associated with an onshore well. In such instances the working conditions of the personnel on the installation can be affected by heave motions of the installation, as well as additional weather conditions. Any delay is costly as the rates of such surface installations are substantial. It is desirable to provide a gauge assembly which is easily and reliably assembled.
International patent application publication WO 2006090123 (Parker Hannifin PLC) describes a sealing connection between an annular sealing means and a tube. Such a sealing connection is well suited for downhole employment. Furthermore, there exists an apparatus for mounting the sealed connection, commercially available and marketed under the name of Phastite (trademark).
Patent application GB2467177 describes a sensing arrangement suitable for oil and gas wells, wherein a sensing fiber is conducted along a tubing into a well and adapted for sensing well conditions.
FIG. 1 shows a prior art solution for establishing a sealed connection between the hollow cable and a gauge housing, as well as an electrical or optical connection between a conductor and a connector. In this solution there exist two sealing sections. In addition, the crew needs to perform a delicate assembly of the numerous parts, sometimes in difficult conditions.